Once a week or twice a month, it is good entertainment, if you like watching movies.

如果你喜欢看电影，一周一次或一个月两次，这是很好的娱乐方式。

youdao

Water the plant once a week if you are to get fruit in the autumn.

如果你想秋天收获果实就要每周给植物浇一次水。

youdao

If you only went out once a week you'd get 'out of shape' during your off days and have to start again from scratch every time.

如果你一星期只出去一回，你会在那天累得没了人形，休整好段时间后，一切又得从头开始。

youdao

So if you go once a week now, you're only going once every two weeks.

WHITEHOUSE: Press Briefing by Deputy Press Secretary Josh Earnest

It depends on if you clean once a week.

BBC: News Online

If you eat fast food once a week, a small switch from French fries to apple fries could save your children almost three pounds of weight a year.

FORBES: 'What Would Batman Eat?' Getting Our Kids To Make Smarter Choices