1 letter

2 mail

3 classifier: 封 fēng

4 to trust

5 to believe

6 to profess faith in

7 truthful

8 confidence

9 trust

10 at will

11 at random

1 information

2 news

3 message

1 recently

2 soon

3 nearest

1 to be convinced (that sth is true)

2 to believe

3 to accept sth as true

1 text message

2 SMS

1 lit. doesn't (even) enter a single aperture (of one's head)

2 I don't understand a word (idiom)

3 it's all Greek to me

1 grasp this fundamental point and all the rest will follow (idiom)

1 to act in collusion (idiom)

1 mutual exchange of assistance (idiom)

2 to benefit from each other's strengths and make up each other's shortfalls

3 to reciprocate with material assistance

4 scratch each other's back

1 He who gives no thought to far-flung problems soon finds suffering nearby (idiom, from Analects).

2 Smug concentration on the here and now will lead to future sorrow.