1．We are accustomed （to/for）using audio to present examples of language in use.

2．Like my friend，I now have an alternative complaining.

3．（what if；so what；how come；what for；what about）
（1）they talked a long time about a painting you weren't that interested in？
（2）—They don't say a single word to each other.
 — ？
（3）—Linda didn't invite us to the party.
 — ？I don't care.
（4）—Please fetch me a piece of paper，Mary.
— ？
（5）playing jokes on Li Ming tomorrow？