好久

wǒ hǎo jiǔ méi kàn jiàn tā le

我好久没看见她了。

I haven't seen her for ages.

hǎo jiǔ méi yǒu shōu dào tā de lái xìn le

好久没有收到他的来信了。

I haven't got a letter from him for a long time.

hǎo jiǔ bù jiàn

好久不见。

I haven't seen you for a long time.

nǐ fǎ yǔ xué le hǎo jiǔ le

你法语学了好久了？

How long have you been learning French?

zhè yào xué hǎo jiǔ cái néng xué huì

这要学好久才能学会？

How long do you need to study this before you pick it up?