(1) CH3CH3 - a 2 carbon alkane. Methane, ethane, propane, butane, pentane, etc., etc. You must learn these.
(2) CH2=CHCH3 - a 3 carbon alkene (double bond). Start numbering from left and change to -ene.
(3)CH3CH2OH - a 2 carbon alcohol. Again, methane(1C), ethane(2C), propane(3C), etc. followed by -ol
(4) CH3COOH - a 2 carbon carboxylic acid. Methane(1C)< ethane(2C), etc. change to -oic acid.
If you still can't name these after trying these hints, re-post and we'll help.