B4

Everybody knows that Christopher Columbus discovered America. Was he really the first to reach the continent? The great Norwegian explorer Thor Heyerdal believed that ancient people were able to build boats that could cross oceans.
(could – прошедшая форма от can)

 CAN

B5

То test his ideas, Heyerdal decided to build a copy of the ancient Egyptian boat and sail across the Atlantic. On May 25, 1969 the boat called Ra left a port in Morocco and headed across the widest part of the Atlantic.
(степень сравнения)

 WIDE

B6

On May 17, 1970 Ra successfully crossed the Atlantic, proving that ancient civilizations had enough skill to reach America long before Columbus.
(Participle I, “доказывая”, подходит по смысловому контексту)

 ^PROVE

B7

In ancient Greece there were many temples built for Apollo. He was the god of youth, beauty, music and poetry. Besides, Apollo had one very special skill — he could see the future. One day Apollo came to the temple in Troy. Among other women he saw Cassandra, a young and beautiful priestess, who worked at the temple.
(woman – ед.ч., women – мн.ч.)

 WOMAN

B8

Apollo was impressed by her grace.
(past simple passive, т.к. он был впечатлён, а не он впечатлил)

IMPRESS

B9

The minute Apollo saw Cassandra, he fell in love. It was love at first sight. Apollo offered her a deal. He would give Cassandra the gift of being able to see the future, if she gave him a kiss. Cassandra agreed.
(past simple, т.к. это случилось тогда, в определённый момент в прошлом, fall-fell-fallen)

FALL

B10

With a laugh, Apollo gave her the gift, dreaming about the reward. Instantly, Cassandra could see the future. She saw Apollo, in the future, helping to destroy Troy.
(Participle I, “мечтая”, подходит по смысловому контексту)

 DREAM