Here are the answers:
X. Complete the sentence with: however, otherwise, therefore.
1. I wanted to go for a walk; however, it started raining.
2. I need to finish this project; otherwise, I won't meet the deadline.
3. She missed her flight; therefore, she had to book another one.
4. He didn't like the book; however, he still finished reading it.
5. I don't like coffee; otherwise, I would have ordered a latte.
6. She forgot her umbrella; therefore, she got soaked in the rain.
7. He needs to practice more; otherwise, he won't be ready for the game.
8. I want to go to the beach; however, it's too cold outside.
9. She's not feeling well; therefore, she's staying home from work.
10. He's allergic to seafood; therefore, he doesn't want to go to the restaurant with us.
XI. Fill in the blank with "however," "otherwise," "therefore," "and," "but," "or," "so," or "because".
1. I wanted to go to the party, but I had to study for my exam.
2. She loves to travel and try new foods.
3. He didn't have any cash, so he had to use his credit card.
4. She needs to exercise regularly because she wants to stay healthy.
5. I love ice cream, but I'm lactose intolerant.
6. He wants to go to the beach, but it's too far from his house.
7. She forgot her phone at home; therefore, she couldn't call her friend.
8. I can't decide what to wear, or I would have been ready by now.
9. He needs to finish his homework; otherwise, he won't be able to watch TV.
10. The restaurant was busy, so we decided to go to a different one.
11. I want to go to the beach; however, it's raining.
12. She wants to go on vacation to Hawaii, or she may choose to go to Mexico instead.