Unit 6 How long have you been collecting shells
Tongue twister 绕口令She sells seashells in the seashore ( 海滨 ), and the seashells she sells are the seashells from the seashore
Do you like shells
Do you like collecting shells
What do you like doing
I like swimming
I started swimming when I entered college
I have been swimming for 4 years
She likes reading
She started reading at 7:00
Now it is 9:00
How long has she been reading
She has been reading for 2 hours
since 7:00
2 hours ago
以来for + 一段时间since+ 时间点一段时间 + agoHe likes teaching
He started teaching in 1981 when he was 20 years old
He is still teaching now
How long has he been teaching
He has been teaching for 30 years
since 1981
30 years ago
he was 20 years old
since+ 从句(一般过去时)45 minutes
They have been playing football for 45 mi