Does the text contain a vague pronoun reference? Did Michael and his brother look through the user manual before trying to fix his computer?

yes, you don't know who's computer it is. is it michael's or his brother's?

the use of “as” in the example to draw the resemblance. some more examples of common similes are given below. common examples of simile. our soldiers are as brave as lions. her cheeks are red like a rose. he is as funny as a monkey. the water well was as dry as a bone. he is as cunning as a fox. simile introduces vividness into what we say.

comfortable

explanation:

one type of the adjectives is predicate adjective. a predicate adjective is an adjective which follows a linking verb and modifies or refers back to the main subject of that linking verb.

it usually is used just before the noun it modies.

here in this example:

'penguins seem comfortable in the coolest habitats', comfortable is the predicate adjective which follows the linking verb 'seem' and modifies the noun.