Is the sentence wrong because it doesn't have "to be"?

Dear all.

In the last sentence of cited report below, I feel confused because this sentence misses the verb "to be" after seems.
If someone knows, please give me an explanation.
I'm looking forwards to your reply.
Your sincerely
Truc





This is transcript of the report
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The European Freshwater Eel


European Freshwater Eel, which look like snakes but are really fish, begin and end their lives in the Sargasso Sea, southeast of Bermuda. As eggs and larvae they drift for three years towards Europe, changing both shape and colour as they reach the fresh-water estuaries of European rivers. They spend the next nine to nineteen years in rivers, streams, lakes and ponds. As they approach old age they seem to have an unexplained compulsion to return to the Sargasso Sea to breed. Many eels which have found their way into ponds and lakes come out of the water and travel overland, gliding through damp grass. When they reach the sea, they make their way to the Sargasso, where they breed and die. No eels make the journey twice. The eel has an acute sense of smell, which is used for navigation in local waters, but inherited memory seems the only explanation for their migration to the Sargasso.

seem - to give the impression of being or doing sth -ALD.

There is no need for BE.

Quote:

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Originally Posted by nhatruc30

Dear all.

In the last sentence of cited report below, I feel confused because this sentence misses the verb "to be" after seems.
If someone knows, please give me an explanation.
I'm looking forwards to your reply.
Your sincerely
Truc





This is transcript of the report
---------------------------------------------
The European Freshwater Eel


European Freshwater Eel, which look like snakes but are really fish, begin and end their lives in the Sargasso Sea, southeast of Bermuda. As eggs and larvae they drift for three years towards Europe, changing both shape and colour as they reach the fresh-water estuaries of European rivers. They spend the next nine to nineteen years in rivers, streams, lakes and ponds. As they approach old age they seem to have an unexplained compulsion to return to the Sargasso Sea to breed. Many eels which have found their way into ponds and lakes come out of the water and travel overland, gliding through damp grass. When they reach the sea, they make their way to the Sargasso, where they breed and die. No eels make the journey twice. The eel has an acute sense of smell, which is used for navigation in local waters, but inherited memory seems the only explanation for their migration to the Sargasso.

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Having read the piece on my own, I would not have found it unusual or necessarily wrong. But I agree that "to be" could have been used and I would not have thought it unusual either. Here is what I found:

"The linking verbs, appear, prove, and seem are sometimes followed by the infinitive to be and a complement (an adjective or noun)."