He spends his spare time (in) learning English.

他业余时间学英语。

youdao

All his spare time has been devoted to learning English over the radio.

他所有的业余时间都花在通过收音机学习英语上了。

youdao

All his spare time has been devoted to learning English over the radio.

他所有的业余时间都花在通过收音机学习英语上了。

youdao