this year than last year一般用什么时态?

this year than last year一般用什么时态? last year 什么时态 There ------pollutions this year than last year. 英语：“this year”用什么时态? this year 用于什么时态 There's_____（little)rain this year than last year. He _________ harder this year than last year. There will be___ pollution this year than last year 1.They produced ____electricity this year than last year. we have ___(little)rainfall this year than last year I study ________hard this year than last year it is much hotter this year than ( ) last year