They are all correct, but the second is not quite natural.
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AnonymousAre they?Strictly, only the last pair: it is the help you appreciate.
Mister Micawber AnonymousAre they?Strictly, only the last pair: it is the help you appreciate.I see. Thanks teacher.
AnonymousWhat about in casual speech, are first two acceptable?As probus said, the second one is not native.