The past perfect is formed by: Had + past participle In the first

sentence you should try to think about it like this: “Man tried to apply for the job,man filled the application form,but the job was already taken.” So the verb refers to a finished action

Was applying could be used if he started to apply but was stopped :

While he was applying a woman asked him a question.

The second statement has to be easier but as an action, think about it like an action that didn’t happened: the phrase it’s not about something that was in progress, so again there’s no use of past continuous form. I might read up on twitter and facebook

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