Question

please answer quickly. 1) I forgot my birthday. My teacher greeted me on that day.. transform into simple sentence 2) what tense should be used in which the sentence starting with the word 'by now',

Answer 1

I forget my birthday, on that day teacher greeted me

Answer 2

There are so many types of sentences from simple sentences to complex sentences and even more complex sentences

A simple sentence is a sentence that obeys the ordinary style of a subject followed by a verb then an object

Simple sentences are easy to construct and convey information directly .so in this case you can say i forgot my birthday when the teacher asked me my name