Filling each of the following blanks with a preposition or an adverb. 1. Students who are not able to register in time for special reasons must ask leave with the relevant certificate. 2. She was having a hard time concentrating in class because she's so tired but she ended with two A's in her first semester anyway. 3. Teenagers who drop of high school have trouble finding decent jobs. 4. The little child looks his mother to cure his hurts. 5. I'm not interested in working part-time as I want to focus my studies at present. 6. I grabbed this opportunity to try my interest in this subject. 7. We can't have the picnic unless more people sign . 8. You may take advantage the summer vacation to do some catch-up job. 9. Years of hard work and perseverance led his final success. 10. Our company didn't begin any venture funding and have developed well ever since.