Unit4 Language points课件(新人教必修2)
Unit4 Language points课件(新人教必修2)第3页

This kind of bird is _________.

dying out

Many traditional customs __________ because they are out of Date.

die away 慢慢消失

He hid behind the door until the footsteps_____________.

have died out

had died away

2.die out (动,植物物种)灭绝