Answer:
1. Donald likes to play tennis and to run cross country.
2. Ginger is a gardener who has first-rate garden tools and who has a beautiful garden.
3. Two things I promise: to work diligently and to succeed.
4. The desk was piled with papers, folders, coffee cups, broken pencils, and two days' worth of half-eaten lunch.
5. He was physically strong and keenly intelligent.
6. They hoped for peace without dishonor.
7. In late March, in April and in May, the weather is warm enough here to begin planting a garden.
Step-by-step explanation:
Parallelism is the use of the same sentence structure or framing so that the grammatical structures of the sentence are not changed. It provides better readability and better understanding for the readers.
1. Donald likes to play tennis and CROSS COUNTRY RUNNING.
Donald likes to play tennis and to run cross country. The use of the word "to+verb" gives it a parallel structure.
2. Ginger is a gardener WITH FIRST-RATE GARDEN TOOLS and who has a beautiful garden.
Ginger is a gardener who has first-rate garden tools and who has a beautiful garden. (who has)
3. Two things I promise: to work diligently and SUCCEED.
Two things I promise: to work diligently and to succeed. (to)
4. The desk was piled with papers, folders, coffee cups, broken pencils, and THERE WERE EVEN TWO DAYS' WORTH OF HALF EATEN LUNCH.
The desk was piled with papers, folders, coffee cups, broken pencils, and two days' worth of half-eaten lunch. (removal of the unnecessary "there were even")
5. He was physically strong AS WELL AS POSSESSING KEEN INTELLIGENCE.
He was physically strong and keenly intelligent. (and+ adverb + ly)
6. They hoped for peace WITHOUT BEING DISHONORED.
They hoped for peace without dishonor. (remove being)
7. IN LATE MARCH, APRIL , AND IN MAY the weather is warm enough here to begin planting a garden.
In late March, in April and in May, the weather is warm enough here to begin planting a garden. (use "in" for the each months)