If you go to Venus, you will discover new things.
And compare it with Earth.
I would say this would classify as a downward comparison as the person is talking about Mark who has a poorer job situation than him and this could be used to bolster the speaker's ego or to knock poor Mark or could just be an observation.
Cohesion in writing means bringing everything your talking about together and making it flow smoothly in your writing.
You did not provide the excerpt but I wound it and the correct answers are the following two sentences:
1.<span>For once, at least, I grasped the mental operations of the Morlocks.
Here we see that they do possess a kind of intelligence, maybe at first strange and unclear but it is there, no matter how strange it might seem.
2.</span><span>I was surprised to find it had been carefully oiled and cleaned.
Here the Time Traveler has found his Time Machine and he finds that the Morlocks had tried to grasp its function and its purpose. They have taken it apart and then cleaned and oiled it, which suggests they know somethings about how the machine work.
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