1.1.14. Complete the following sentences using correct forms of be: 1. Jack almost certain of it. 2. We... not quite sure of it. 3. She... undecided how to refuse. 4. We... uncertain about what to do. 5. I... always careful about whom to deal with. 6. Your project... sure to succeed. -To succeed? On the contrary, it... certain to fail! 7. They... undecided how to cancel the appointment. 8. The result... too doubtful to be sure of it. 9. The weather... not very good today. It... sure to rain. 10. My friends... sure to do all the assignments. 11. Robert and I... undecided whether to work or to have fun

Вот решения с подробными объяснениями. Задача — поставить форму глагола to be (am/are/is) в зависимой от подлежащего позиции и использовать правильное прилагательное в связке. Правило (кратко): в таких предложениях выполняется связка “be” + прилагательное, которое описывает отношение говорящего к ситуации. Форма "to be" зависит от числа и лица подлежащего: - I → am - you/we/they → are - he/she/it/Name → is 1) Jack is almost certain of it. - Обоснование: Jack — единственное число, третье лицо. Используем is. 2) We are not quite sure of it. - Мы/We — множественное число. Используем are. 3) She is undecided how to refuse. - She — она, единственное число. Используем is. 4) We are uncertain about what to do. - We — множественное число. Используем are. 5) I am always careful about whom to deal with. - I — первое лицо, ед. число. Используем am. 6) Your project is sure to succeed. - Your project — единичное; используем is. “sure to” означает, что носят позитивный прогноз: проект наверняка добьётся успеха. - To succeed? On the contrary, it is certain to fail! - Здесь тоже подлежащее “it” (неявно about the project), снова единственное число: используем is. Полная форма: "To succeed? On the contrary, it is certain to fail!" 7) They are undecided how to cancel the appointment. - They — множественное число. Используем are. 8) The result is too doubtful to be sure of it. - The result — единственное число. Используем is. 9) The weather is not very good today. It is sure to rain. - The weather — союзное существительное в единственном числе. Используем is. Затем повторяем с местоимением It: It is sure to rain. 10) My friends are sure to do all the assignments. - My friends — множество, поэтому are. 11) Robert and I are undecided whether to work or to have fun. - “Robert and I” — две личности, форма множественного числа: are. Итоговый набор заполненных предложений: 1) Jack is almost certain of it. 2) We are not quite sure of it. 3) She is undecided how to refuse. 4) We are uncertain about what to do. 5) I am always careful about whom to deal with. 6) Your project is sure to succeed. - To succeed? On the contrary, it is certain to fail! 7) They are undecided how to cancel the appointment. 8) The result is too doubtful to be sure of it. 9) The weather is not very good today. It is sure to rain. 10) My friends are sure to do all the assignments. 11) Robert and I are undecided whether to work or to have fun. Если хочешь, могу добавить краткие заметки по каждому прилагательному (certain, sure, undecided, uncertain, careful, doubtful) и объяснить их оттенки смысла.