Be afraid to do и be afraid of – ing
I am afraid to do something = Я не хочу что-то делать, поскольку это небезопасно или результат действия мне нежелателен:
– The streets in this city are not safe at night. Many people are afraid to go out alone.
– She was afraid to tell her parents that she had broken the neighbour’s window.
I am afraid of something happening = возможность, что случится нечто нежелательное:
– We walked along the path very carefully because it was icy and we were afraid of falling.
– I don’t like dogs. I’m always afraid of being bitten.
Итак, you are afraid to do something, потому что you are afraid of something happening в качестве результата. Сравните:
– The boys were afraid to play football in the garden
– I was afraid to stay in the sun because I was afraid of getting burnt.
Need to do и need – ing
I need to do something = мне надо что-то сделать:
– I need to take more exercise.
– He needs to work harder.
– I don’t need to come to the meeting, do I?
Need – ing = необходимость делать что-то :
– The batteries in this radio need changing.
– This jacket is rather dirty. It needs cleaning.
– Do you think the grass needs cutting?
За help следует инфинитив с to или без:
– Everybody helped clean up after the party.
– Can somebody help me move this table?
Существует выражение `can’t help doing something.’
I can’t help doing something = Я не cмог удержаться, чтобы не сделать этого:
– I tried to be serious but I couldn’t help laughing.
– I’m sorry I broke the glass. Someone pushed me and I couldn’t help dropping it.
– He is stupid but it’s not his fault. He can’t help being stupid.