Add spaces: ByDecember1936shewasforcedtotakesickleavewhichwassupposedtoendinAugust1937sothatshecouldtakeupteachingagainfortheacademicyear1937-38.

Answer: By December 1936 she was forced to take sick leave which was supposed to end in August 1937 so that she could take up teaching again for the academic year 1937-38.

Add spaces: Hehadmouseinhispocket,whichheplayedwithandcaressed,butkilledthemousebymistakewithoutanunderstandingofwhathe'sdone.

Answer: He had mouse in his pocket, which he played with and caressed, but killed the mouse by mistake without an understanding of what he's done.

Add spaces: ImeetShirleyWonginHongKongafewdaysafterthechildren'smeetingattheconference.

Answer:
I meet Shirley Wong in Hong Kong a few days after the children's meeting at the conference.