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Talking About Your Experience in an English Interview: Ten Sentences for Introductions, Projects, Failures, and Questions

Expertise: I have experience in / as. Current job: I currently work for a company that…. Ownership: I was responsible for + -ing. Results: reduced … from A to B. Difficulty: The hardest part was + -ing. Reflection: I underestimated how…. Change: Since then, I've always…. For your own questions, ask how the team divides up the work and what the goals are for the first three months.

Chatting About a Job Hunt in English: Six Places My Sentences Got Stuck

My friend understood me, but the same six things kept going wrong: use Have you + past participle for 'so far' questions; apply to a company, apply for a job; interview + a person means you are the interviewer; other takes a plural noun while others stands alone; because takes a clause and because of takes a noun; adjectives need be, and sentences need a subject.

Reporting Progress, Saying You're Stuck, and Asking for Help: Ten Sentences for Work

Report finished work with the past simple plus a time; say I'm still waiting for when you are waiting; use by for a deadline; say I'm stuck on for a blocker; ask with Could you take a look at… when you have a moment; soften disagreement with I'm not sure about… and then suggest with Could we…; estimate with This will probably take….

AI Engineering from Scratch: A Guide to the Free Course That Builds Everything by Hand, from Linear Algebra to Multi-Agent Systems

AI Engineering from Scratch is a free, MIT-licensed course on GitHub with about 63k stars: 20 phases and 523 lessons, running from linear algebra, classical ML, and deep learning to LLMs, agents, and AI safety. Each lesson builds the algorithm by hand, then repeats it with a framework. The early math and deep-learning-core phases are worth following step by step; skip the Phase 10 SFT/RLHF/DPO lessons, and treat the rest as a map of topics.

Connecting Courses by Hung-yi Lee, Hsuan-Tien Lin, and Yun-Nung Chen | Global AI/CS Course Map

National Taiwan University spreads its AI/ML courses across Electrical Engineering and Computer Science, and an official 'Machine Learning and AI' specialization stacks them into four levels. Hung-yi Lee's courses are the most open: ML 2026 Spring and Intro to GenAI and ML 2025 Fall publish slides, recordings, homework PDFs, and Colab notebooks, with only grading held back. Hsuan-Tien Lin's lectures are fully recorded and his Fall 2024 HW0–HW7 remain on the course page; Yun-Nung Chen's lectures are fully recorded, but most homework is public only as walkthrough videos; and since August 2025 Coursera only lets free learners watch the first module.

Taiwan AI Open Courses Beyond NTU: Using TAICA's Course Lists to Find NTHU, NCCU, NCKU, and NTUT Classes | Global AI/CS Course Map

Most public AI courses in Taiwan outside NTU come from TAICA, an alliance set up by the Ministry of Education. Each semester's course list says where every flagship course streams, and courses that stream on YouTube are usually watchable by anyone. Two courses are complete enough to self-study: Hung-Yu Kao's Natural Language Processing at NTHU (Fall 2025) and Yen-Lung Tsai's Generative AI at NCCU (Spring 2025), both A3. Wei-Ta Chu's Introduction to AI at NCKU, Ping-Hsuan Han's Human-AI Interaction at NTUT, and Min-Chun Hu's Robotic Navigation and Exploration at NTHU have full recordings but keep assignments on NTU COOL, so they rate A2. NYCU's TAICA courses are taught in English; the Deep Learning recordings are not publicly listed and Physical AI has just started, so neither made the main table.

Three Versions of CS189: Spring 2026 as the Base, Spring 2025 as the Classic, Fall 2026 in Progress | Berkeley CS189 Course Map

Several semesters of Berkeley CS189 are online at once. From here on, this series follows Spring 2026 (Listgarten/Dimakis): its slides, 25 lecture videos, discussions with solutions, HW1–5 handouts and midterm solutions are all publicly accessible, so it rates A3. Spring 2025 (Shewchuk) is a different, classic route and the only one that covers SVMs, decision trees, PCA and boosting. Fall 2025's homework folders open empty to outside readers, so it was not chosen. Fall 2026 is still running and serves only as a comparison.

Linear Algebra / Calculus / Probability Warm-up + Fashion Coding | Berkeley CS189 Assignment 1

CS189 Spring 2026 HW1 has three pieces: ten written math warm-ups (a linear system, limits of matrix powers via eigendecomposition, SVD, a matrix that flips an image, partial derivatives, a chain rule over a recursion, and four probability problems including Bayes for cancer screening), plus two public Modal notebooks on Fashion-MNIST. Part 1 drills pandas / Plotly / K-means / an MLP / matrix-based image augmentation / tensor puzzles; Part 2 does price regression, MAE / MSE / R², confusion matrices, and finally a secret test set whose images have been rotated. Due Feb 20; no official solutions.

Chatbot Arena Paper Questions, Regression, MLE/MAP, From GMMs to Flow Matching | Berkeley CS189 Assignment 2

HW2 is a written-only assignment with 10 problems. The first half practices reading a paper (Chatbot Arena) and the core derivations for regression and MLE/MAP. The two heaviest problems come last: Mixed Feelings goes from k-means' fragility to outliers through robust k-means to a GMM with a uniform background, and Watch Me Flow Dat proves that conditional flow matching and a discretized MLE are the same objective. The problem PDF and LaTeX template are freely downloadable; there are no official solutions.

Autograd from Scratch (BearTensor), Newton's Method, and the Information Bottleneck | Berkeley CS189 Assignment 3

HW3 has two halves. The four written problems run from Newton's method for logistic regression and a convergence analysis of coordinate descent, through backprop, VJPs, and implicit differentiation, to an information-bottleneck view of what deep networks compress. The notebook has you build a BearTensor computation graph in NumPy, topological-sort backprop, and SGD/Momentum/Adam, then train a red-wine quality regressor with it, plus an optional Muon optimizer. Problems and notebook are public; official solutions and hidden tests are not.

ResNet/Transformer Paper Questions and Implementing CNN, ResNet, Transformer, DNABERT, and ConvNeXt | Berkeley CS189 Assignment 4

HW4 has three pieces. The written part has you read ResNet and Attention Is All You Need in the order problem → existing work → proposal → method → contribution. The 4.1 notebook builds a CNN and ResNet-18 in PyTorch, then assembles an encoder-decoder transformer step by step from softmax, trains it on TinyStories, and generates stories. The 4.2 notebook cuts DNA into 6-mers for a pretrained DNABERT to classify species, and turns audio into spectrograms for ConvNeXt, comparing training from scratch, a frozen backbone, and full unfreezing. Two Kaggle competitions; due 5/1. Outside readers get the problems but not the course data bundle or tests.

(Optional) Guide: InfoNCE for Biology, Diffusion Theory, LLM Fine-Tuning + Kaggle | Berkeley CS189 Assignment 5

HW5 is the only Spring 2026 assignment marked optional, due 5/11, the same day as the final. The written part has three pieces: derive InfoNCE gradients and the trade-off in the number of negatives, using scRNA-seq as the setting; prove the optimal denoiser is a conditional expectation and derive the continuity equation; generalize flow matching's straight-line path to arbitrary interpolations. The notebook is a full LLM fine-tuning pipeline: Qwen2.5-0.5B-Instruct is fixed, MMLU machine_learning is converted to chat format, TRL's SFTTrainer does full fine-tuning, accuracy on CS189 exam questions is compared before and after, and predictions on a 169-question test set go to Kaggle, all while guarding against catastrophic forgetting. An official hw5-sol.pdf is provided, covering the written part only.

ML Problem Framing, Data Tools, Terminology and Techniques | Berkeley CS189 Lectures 1–3

The first three lectures of CS189 Spring 2026 hold off on derivations. They teach you how to tell whether a problem calls for ML, how to look at data with pandas and Plotly, and how to run one full train/validate/test cycle in scikit-learn. Lecture 1 has slides but no recording; Lectures 2–3 have slides and video; Discussion 1 is a calculus, linear algebra and probability warm-up with solutions and a walkthrough. Together they set you up directly for HW1.

K-means, Probability Review, MLE, Multivariate Gaussians and GMMs | Berkeley CS189 Lectures 4–7

Lectures 4–7 of CS189 Spring 2026 tie unsupervised learning into one thread. K-means clusters the data, then its weaknesses show up: hard assignments, no probabilistic framing, and a bias toward round clusters of similar size. The course reviews probability, introduces maximum likelihood estimation (MLE) and multivariate Gaussians, and rewrites K-means as a Gaussian mixture model (GMM). The GMM log-likelihood has no closed-form solution, and that gap leads the course to gradient descent. All four lectures have slides and video; Discussions 2–3 come with solutions and walkthroughs.

Linear Regression, the Geometry of Least Squares, and Regularization | Berkeley CS189 Lectures 7–10

Over four lectures, CS189 Spring 2026 presents linear regression from three angles that meet in one formula: MLE under Gaussian noise is least squares; the least-squares solution is the orthogonal projection of y onto the column space of X; and when features are collinear or too many, ridge (the MAP estimate under a Gaussian prior) or lasso (a Laplace prior) pulls the solution back, with λ chosen on a validation set. Slides, videos, and Discussion 3–4 solutions are all publicly accessible.

Classification, Generative Classifiers, Logistic Regression, and ROC | Berkeley CS189 Lectures 11–12

CS189 Spring 2026 Lec 11–12 splits classification into two routes. Generative models fit p(x|y) for each class (GDA: shared covariance gives LDA and a linear boundary, per-class covariance gives QDA and a quadratic one). Discriminative models fit p(y|x) directly (logistic regression: sigmoid, softmax, cross-entropy MLE, no closed form, so gradient descent). The bridge: the LDA posterior can always be written in logistic form, but not the other way around. For evaluation, accuracy misleads under class imbalance; ROC/AUC sweeps every threshold and ignores calibration; PR curves care about class balance.

& 15: Convergence, Momentum, Adam, SGD | Berkeley CS189 Lecture 13

CS189 Spring 2026 covers gradient descent in two lectures. Lec 13 derives the learning-rate limit and the condition number from the Hessian's eigenvalues, then moves through momentum, learning-rate schedules, AdaGrad/RMSProp/Adam, and mini-batch SGD. In Lec 15, Dimakis walks through the same material again, starting from a gradient computed by hand on a small data table. Both slide decks, the recordings, Lec 13's handwritten notes, and Discussions 6 and 7 (with solutions) are all publicly accessible.

& 16: MLE vs MAP, Bias-Variance, Entropy and KL, Plus a Midterm Self-Check | Berkeley CS189 Lecture 14

Lec 14 recasts ridge as MAP under least squares plus a Gaussian prior, breaks down bias-variance, and closes by using Chatbot Arena to show how to read a paper. Lec 16 builds entropy from compression, moves on to KL and cross-entropy, and lands back on the logistic regression loss. The 3/17 midterm and its official solutions are public in the past-exams folder, with 6 problems, 56 points, 110 minutes, and 6 problem-by-problem walkthrough videos, so you can sit it as a mock exam.

Depth, Universal Approximation, Activations, and Backpropagation | Berkeley CS189 Lectures 17–18

Lec 17 uses XOR to show that a linear model, and even a stack of linear layers, cannot learn a nonlinear boundary, while one ReLU layer can. The universal approximation theorem guarantees that a network exists but not how to find its weights or how wide it must be. Lec 18 turns the chain rule into backpropagation on a computation graph: gradients from multiple paths add up, and the cost is linear in the number of parameters, versus quadratic for finite differences. Discussion 8 has you prove a GD convergence rate and 1-D ReLU universal approximation yourself.

Initialization, BatchNorm, CNNs, Early Stopping, and Double Descent | Berkeley CS189 Lectures 19–20

Lec 19 wraps up backprop, then tackles how to keep gradients flowing: all-zero initialization makes every unit learn the same thing, so use small random values (He init for ReLU), and batch norm normalizes pre-activations with mini-batch means and variances. The second half introduces CNNs: local connectivity plus weight sharing lets one feature detector scan the whole image. Lec 20 finishes pooling, receptive fields, and CNN training, then covers early stopping, dropout, and double descent, which breaks the classic bias-variance picture.