Questionnaire

a. Interest in English class
b. Interest according to each skill
c. The most difficult part among 4 skills
d. Interest in the most important part among 4 skills
e. Studying English after school
f. Understanding in the classroom
g. Study materials (all)
h. The use of study materials
i. View on the process of English class
j. Favorite type of activities

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Are they suitable for the titles of questionnaire

I'm not sure what you mean. You're looking for ONE that will serve as a title for a whole questionnaire? Or are these intended to be sections of questions in the questionnaire?

The provided list of items appears to be a set of questions or topics that could be included in a questionnaire about English class. Let's go through each item to determine if they are suitable as questionnaire titles:

a. Interest in English class - This can be a suitable title as it asks about the respondent's level of interest in the English class overall.

b. Interest according to each skill - This title suggests that the questionnaire will inquire about the respondent's interest in each individual skill in English, such as reading, writing, speaking, and listening. It is suitable as a title.

c. The most difficult part among 4 skills - This title implies that the questionnaire will focus on identifying the most challenging skill among the four language skills: reading, writing, speaking, and listening. It is an appropriate title.

d. Interest in the most important part among 4 skills - This title indicates that the questionnaire aims to gauge the respondent's interest in the skill that is considered the most vital among the four skills. It is an acceptable title.

e. Studying English after school - This item appears to be a topic or question itself, rather than a title for a section of the questionnaire. It may need to be revised to be more explicitly applicable as a section title.

f. Understanding in the classroom - This title suggests that the questionnaire will explore the respondent's level of understanding or comprehension in the classroom setting. It is a suitable title.

g. Study materials (all) - This item seems more like a category or topic heading for questions related to study materials. It might not serve as an adequate section title on its own.

h. The use of study materials - This title implies that the questionnaire will examine how study materials are utilized by the respondent. It can be considered a suitable title.

i. View on the process of English class - This title suggests that the questionnaire will seek the respondent's perception or opinion on the overall process of the English class. It is a suitable title.

j. Favorite type of activities - This item seems to be another individual question or topic rather than a section title. It could be adjusted to fit as a section title related to activities or preferences.

In summary, some of the items in the list are suitable as questionnaire titles, while others may need some revision to better serve as section titles within the questionnaire.