There is the passage

The weather was a powerful force in the lives of the Norse

Explanation:

'at the mercy of' suggests that they had so control over it, it was something that affected them no matter what they could've done against it. It shows that they had to either stay and let it make they lives a great deal harder or leave and look for a safer area to live out their lives.

the sentence does not violate the phrase structure second rule (introduced by noam chomsky) because noun phrases consist of a determiner such as a, the or every, and a noun. in the sentence, the noun phrase the cake includes a determiner (the) and a noun (cake).

on the other hand, the first rule indicates that a sentence encloses a noun phrase, followed by a verb phrase. the example sentence can be analysed as follows:

john (n) + ate (v) + the (det) + cake (n).

onto a large boat, and mark the water level that the boat sinks to. then, take the elephant out and put a bunch of marked weights onto the boat until it reaches the same water level. add up the masses of the weights to get the weight of the elephant.