sth occurred to sb中occur为什么是ed?和时态有什么关系?

sth occurred to sb中occur为什么是ed?和时态有什么关系? it occurred to sb that... 造句：hard sb sth/sth to sb .sell sb sth/sth to sb lend sb sth/sth to sb serve sb sth/sth to sb s造句：show sb sth/sth to sb .offer sb sth/sth to sb .take sb sth/sth to sb .owe sb sth/sth to sb.teach sb sth/sth to sb.pass sb sth/sth to sb .tell 英语语法中,need sb sth是need sb to do 还是need sb do /doing sth? give sb.sth=give sth to sb 中,.sb若是代词,用前面哪个短语? ask sth to sb ask sb sth sth to sb 还是 sth for sb hand sb.sth (hand sth to sb.) donate sth to sb中sth充当什么语,to sb充当什么语? give sth.to sb. send sth.to sb. sth.happen to sb. owe sth to sb Teach sth.to sb. be sth to sb offer sth.to sb recommend sth/sb to lend sth to sb.