Ladies and gentlemen, good morning: -Good morning, ladies and gentlemen:
give you a speech.-make a speech(give you a speech is Chinglish)
the midterm examinations. I didn’t do well in it. -it改为them因为前面是examinations
I have failed. 既然是上周的事，这里应该用failed，另外，为了与上文衔接，最好再加上and thus，即and thus I failed.
I believe myself and try my best.-I believe in myself and will surely try my best.
that if who smiles till the last, who smiles best! -that he who smiles till the end smiles best.