... than he. (Remember that "him" is for objects and "he" is for subjects.)
In the second sentence, "still" carries the meaning of "you continue to be" ...
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In the last sentence, what is the meaning of 'still'? Is still the same as 'much, or 'far' emphasizing the comparative sentence? Or does 'still' mean the definition 'used when saying that something continues to be the same as before, or has not happened yet' as in the Longman dictionary?
In the second sentence, "still" carries the meaning of "you continue to be" ...
When it says "you are still smaller than him," it means that even after the frog blew himself up, you are still smaller in size than the frog. In this case, "still" confirms that the position or state of being smaller has not changed, despite the frog's attempt to appear bigger. It aligns with the definition you mentioned from the Longman dictionary, where "still" refers to something continuing to be the same as before.