Question

用by the time和before造两个完成时的句子

Answer 1

He had left Chine by the time when he was 40 years old.
He had left Chine before he was 40 years old

Answer 2

By the time I got outside, the bus had already left
i've never met you before

Answer 3

你好！
By
the
time
I
got
outside,
the
bus
had
already
left
i've
never
met
you
before
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