Проверь на ошибки: 1. Oh, no! Look at those cars! They are going to crash! 2. What shall I do tomorrow? I know! I'll paint the kitchen. 3. I'm sure you will enjoy the film if you go and see it. 4. Lynne has just sold her car. Is she going to buy a new one? 5. I could lend you some money if you like. Could you? I will pay you back on Friday. 6. On Thursday evening I am meeting my friend Julie at 7 o'clock. 7. Be careful! You are going to break that glass. 8. I have got an appointment with the doctor on Friday, I am seeing him at 6.30 o'clock. 9. It is going to snow later at night. 10. Look out! You are falling. 11. I am having dinner at 7.00. 12. The conference starts on June 3rd and finishes on June 10th.

Ваши предложения в целом написаны правильно, но есть некоторые небольшие ошибки в пунктуации и структуре фраз. Вот исправленный вариант: 1. Oh, no! Look at those cars! They are going to crash! - (Верно) 2. What shall I do tomorrow? I know! I'll paint the kitchen. - (Верно) 3. I'm sure you will enjoy the film if you go and see it. - (Верно) 4. Lynne has just sold her car. Is she going to buy a new one? - (Верно) 5. I could lend you some money if you like. Could you? I will pay you back on Friday. - (Смысловая связка здесь подразумевает, что это ответ на предложение, так что всё верно) 6. On Thursday evening, I am meeting my friend Julie at 7 o'clock. - (Добавлена запятая после "evening") 7. Be careful! You are going to break that glass. - (Верно) 8. I have got an appointment with the doctor on Friday; I am seeing him at 6:30. - (Используйте точку с запятой вместо запятой, и правильное написание — 6:30, без "o'clock") 9. It is going to snow later at night. - (Верно) 10. Look out! You are falling. - (Верно) 11. I am having dinner at 7:00. - (Используйте 7:00, без "o'clock", если хотите сохранить стиль) 12. The conference starts on June 3rd and finishes on June 10th. - (Верно) Общая оценка: предложения в основном корректные, однако стоит обратить внимание на небольшие нюансы пунктуации.