1 She said she was working in a restaurant then.
S+ say/ said+ (that)+ S+ V.
2 Unless the man arrives, we will start the conference without him.
Unless+ S+ V, S+ will/can/shall+ V
3 It’s difficult to speak English fluently.
Adj+ to V.
4 They haven't visited me for 5 years.
S+ last+ Vp2 = S+ haven't/ hasn't + Vp2
5 The last time I went to London was when I left my college.
S + HTHT (phủ định) + since / for + …..
= S + last + QKĐ (khẳng định) …+ when + mệnh đề
= The last time + S + QKĐ (khẳng định) + was + thời gian
6 Although the hotel was noisy, we stayed there.
Despite/In spite of+ Noun/Noun Phrase/V-ing/ the fact that, S+ V+…
= Although/ though/ even though+ clause.
7 Our house was bought by us last year.
8 If Mr. Pike didn't use energy-saving bulbs, he wouldn't save a lot of money.
9 I suggest taking the train.
10 If she wasn't ill, she could go to school today.
11 Green trees were planted around their house.
12 Lan wishes she had a sister.
13 Peter asked Ann what she had written the day before.
14 She began working for a company in Ha Noi 10 years ago.
15 Minh spends 2 hours doing his homework every day.
16 Because it rained heavily, we were late for school.
17 Their house was built last year.
18 Ba asked Lan if she wanted a cold drink.
19 My elder brother has learned English for 3 years.
20 She said she was working in a restaurant and didn't care much for it.