我有事要做 I anything to do

我下午有事要做 It is necessary to do something I p.m

有意要做某事 mean to do

对某人没有必要做某事 There's no need for sb. to do

有许多事情要做 There's a lot to do ; tener mucho que hacer

有必要做某事 be necessary to do sth ; need to do sth ; It's necessary to do sth ; need to do sth./need do sth

有事情要做 There are things to do ; Things to do

没有必要做某事 There is/was no need to do sth ; There is no need to do

感觉有必要做某事 feel obliged to do sth