bài 1 : 

1 : my mother used to tell me stories before i went bed

meaning : mẹ thường kể chuyện trước khi tôi đi ngủ

2 : you better take the keys in case im not out

in case + mệnh đề : trong trường hợp..

3 : my mother like eating friend chicken although it's very bad for his health

although thường dùng để nối hai mệnh đề đối lập nhau

4 : yesterday, jim was playing the piano while his sister was playing the flute

meaning : ngày hôm qua, jim đang chơi piano trong khi / thì chị anh ấy đang chơi sáo

5 : you shouldnt spend too much on computer as it is harmful to your eyes 

as + mệnh đề : chỉ nguyên nhân hoặc lí do

6 : i will phone you as soon as i get there

7 : the scientist usually works in his lab until the sun sets

until : cho đến khi

8 : unless you promise not to tell lies again, i wont forgive you

meaning : trừ khi bạn không nói dối một lần nào nữa, tôi sẽ tha thứ cho bạn

9 : even if her legs were hurt, she made attempt to finish the running track

even if : ngay cả khi

10 : she talked as if she witnessed the accident. but in fact she knew nothing

as if : cứ như là

11 : i didnt finish my homework since i was seriously ill yesterday

since + mệnh đề : bởi vì

12 : james decided to save money from now so that he has enough money to travel this summer

so that + mệnh đề : chủ mục đích

13 : once we have been friends for only one year, we deeply understand each other

once : một khi

14 : câu này k có đáp án, cậu hỏi lại giáo viên xem sao

15 : i was cycling home yesterday when i saw jim standing near the foundtain

meaning : tôi đang đạp xe về nhà thì thấy jim đang đứng cạnh đài phun nước

bài 2 :

1 : when jim came house, he realized that someone had broken into his house

2 : you'd better bring your raincoat in case rain pour down

3 : they have been colleagues since they graduated

4 : unless tim put more effort in his studying, he wont catch up with his classmates 

5 : my mother always reminds me to wash my hands before i have meals 

6 : we will go picnicking as long as the weather is fine

7 : james behaved as though nothing has happened

8 : i cant make it on saturday because i will be fully occupied

9 : when i got home my father was moving the lawn while my mother was watering the flowers beds

10 : although i dont get on well with mary, i really admire her inteligence and beauty

bài 4 : 

1 : g - until : cho đến khi

2 : a - quá khứ tiếp diễn -> quá khứ đơn

3 : f - câu điều kiện loại 1 (if; s; vs; es / s will; may; can v)

4 : c - quá khứ hoàn thành trước quá khứ đơn

5 : b - though : mặc dù

6 : h - it's + time + since quá khứ đơn

7 : e - so that : để 

8 : d - even if : thậm chí nếu, dù cho

bài 4 : 

1 : jim was absent from class yesterday. he was suffering from a bad cold

=> jim was absent from class yesterday because he was suffering from a bad cold

2 : they decided to move their house. they dont have a travel a long distance to work

=> they decided to move their house so (so that) they dont have to travel a long distance to work

3 : mary hurt her fingers yesterday. she was preparing dinner (câu này cậu sửa từ heard -> hurt nha)

=> mary hurt her fingers yesterday while (when) she was preparing dinner

4 : at 4pm yesterday, my mother was cleaning the house. i was looking after my younger brother

=> at 4pm yesterday, my mother was cleaning the house while i was looking after my younger

5 : they decided to go an excursion. they want to get away from work stress

=> they decided to go an excursion since / because they want to get away from work stress 

nếu được thì cho tớ tlhn, 5sao và cảm ơn ạa <3