Give the correct form of the verbs:
1. My friend promised (return) _to return_______________ the book very soon.
2. Most people enjoy (write) ___writting_____________ letters to their friends.
3. Tom avoids (study) _______studying_________ his lessons as long as possible.
4. David finished...
1) If you..had checked.........(to check) the car, it (not/to break) wouldn"t have broken down in the middle of the desert.
2) If it.hadn't rained.........(not/to rain), the children (to play) would have played outside.
3) If my parents ..hadn't been.........(not/to be) so tired...
1/ If you are kind to me, I (be) will be_____ good to you.
2/ He (come) _would come_____ if you waited.
3/ If you (ring) rang_____ the bell, the servant would come.
4/ If I had known that the baby was hungry, I (feed) __would...
Cho tam giác ABC(AB<AC), đường cao AH. Gọi M, N, P lần lượt là TĐ của các cạnh BC, CA, AB
a) Cm: Np là đg trung trực của AH
b) CM: MNPH là hình thang cân
C) Xét trường hợp đặc biệt khi tam giác abc là tam giác cân thì có kết luận gì về tứ giác MNPH?