I have read your comment on the use of recommend and suggest and I must say your explanation flabbergasts me. That is how you say it correctly: His doctor recommended/suggested that he exercise more. If you recommend something then "should" is not necessary or almost incorrect, because its a recommendation and not obligation! If you use should then you are not recommending anymore! This applies to all your examples:
He recommended that my friend visit Northern Avenue in Flushing if he wants to get good Korean food. I recommended that he go to the Bronx Zoo on Wednesday because it is free day there. They suggested that we avoid going to certain areas of the Bronx because they have been neglected by city hall and are very dangerous.
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