时而

1. from time to time; sometimes

♦ 天上~飘过几片薄薄的白云。 Every now and then fleecy clouds floated across the sky.

2. (used reduplicatively) now...now...; sometimes... sometimes...

♦ 这天气变化无常, ~晴天, ~下雨! What changeable weather, fine one moment, raining the next!