Exercise 44 Page 614

The first and the second part of the statement say that

\overline{E F} ≅ \overline{P Q},

and

\overline{P Q} ≅ \overline{U V} .

This means that the full statement must be

If \overline{E F} ≅ \overline{P Q}, and \overline{P Q} ≅ \overline{U V}, then \underline{\overline{E F}} ≅ \underline{\overline{U V}} .

This is because the first two statements say that we have two objects,

\overline{E F}

and

\overline{U V},

that are both the same as a third object

\overline{P Q} .

If the two object are the same as a third object, they must be the same as each other as well.