TRÍ ĐỨC ENGLISH - Bài 19: Present Perfect vs Simple Past (How long / When / Since / For) TRÍ ĐỨC ENGLISH Chuyên nghiệp · Tận tâm · Bứt phá 📘 BÀI 19: PRESENT PERFECT vs SIMPLE PAST (How long / When / Since / For) ❓ a) Phân biệt: How long vs When 🌧️ When did it start raining? → It started raining at one o'clock. ⏰ How long has it been raining? → It has been raining since one o'clock / for an hour. 📌 Quy tắc quan trọng: Simple Past (I did) → dùng để hỏi hoặc nói WHEN một việc xảy ra (thời điểm cụ thể trong quá khứ). Present Perfect (I have done / I have been doing) → dùng để hỏi hoặc nói HOW LONG một việc đã diễn ra (tính đến hiện tại). 💑 When did Tom and Ann first meet? → They first met when they were at school. 💑 How long have Tom and Ann known each other? → They've known each other since they were at school. 📅 b) Since và For 🌟 SINCE + thời điểm bắt đầu (mốc thời gian) 🌟 FOR + khoảng thời gian (độ dài) ──────┬──────────────────────────────────▶     8 o'clock            for two hours       now 📌 I've been waiting for you since 8 o'clock . (mốc thời gian) 📌 I've been waiting for you for two hours . (khoảng thời gian) 📌 since 1977 / since Christmas / since lunch time / since we arrived 📌 for two hours / for ten...