Guru menilai soalan-soalan pelajar secara ringkas selepas kelas.

Yes. Reduplication with a hyphen commonly marks plurality or variety in Malay. So soalan-soalan emphasizes “questions (more than one).”

• Without reduplication, soalan can still be understood as plural from context.
• If you use a number or quantifier, do not reduplicate: tiga soalan, banyak soalan, beberapa soalan.

By default, pelajar is number-neutral. To make it explicit:

• Singular: seorang pelajar (one student)
• Plural (people): para pelajar (the students, formal), or pelajar-pelajar (reduplication)
• With quantifiers: ramai pelajar (many students), beberapa orang pelajar (several students) Note: Don’t combine para with reduplication (avoid para pelajar-pelajar).

Malay uses a “possessed + possessor” noun-noun sequence: soalan-soalan pelajar = “students’ questions.”
You can say soalan daripada pelajar to emphasize origin/source (“questions from students”), which is also natural here. The nuance is:

• soalan pelajar: possessive/attributive
• soalan daripada pelajar: source/origin

Menilai means “to evaluate/assess/judge.” It’s perfect for assessing work, performance, or quality: menilai tugasan, menilai jawapan, menilai pelajar.
For handling questions, more natural options are:

• Answering: menjawab soalan-soalan pelajar
• Discussing: membincangkan soalan-soalan pelajar
• Marking/Checking (work): menyemak or menanda So if the teacher addressed the questions, menjawab or membincangkan would be a better verb than menilai, unless you really mean “evaluate the quality of the students’ questions.”

Root: nilai (“value”).
Prefix: meN- forms an active transitive verb. With a base starting in n, meN- surfaces as men-, hence menilai.
Examples of this pattern:

• menilai (meN- + nilai)
• menulis (meN- + tulis; t drops)
• mengajar (meN- + ajar; vowel triggers meng-)

Secara turns an adjective/noun into an adverbial “in a … manner.” Ringkas = “concise/brief,” so secara ringkas = “briefly.”
Alternatives:

• dengan ringkas (also good)
• secara sepintas lalu (cursorily, “in passing”)
• To stress “only briefly”: secara ringkas sahaja Note: sekejap/sebentar mean “for a short time” (duration), not “in a concise manner.”

Malay doesn’t mark tense on the verb. Time is inferred from context or time words like selepas kelas. To make it explicit:

• Completed: Guru sudah/telah menilai …
• Progressive: Guru sedang menilai …
• Future: Guru akan menilai …

Yes. Word order is flexible:

• Selepas kelas, guru menilai … (fronting for emphasis)
• Guru menilai … selepas kelas. (neutral) Synonyms:
• sesudah (formal), lepas (colloquial) So: Sesudah kelas, or colloquially Lepas kelas.

Yes:

• Guru menilai soalan-soalan pelajar secara ringkas selepas kelas. (most common)
• Guru secara ringkas menilai soalan-soalan pelajar selepas kelas. (adverb after subject) Avoid splitting verb and object unnecessarily: Guru menilai secara ringkas soalan-soalan pelajar … is possible but less smooth.

Both are correct:

• pelajar-pelajar: plural via reduplication
• para pelajar: human-plural collective, formal/neutral Don’t combine them together. Note that para is only for humans.

Use the di- passive:

• Soalan-soalan pelajar dinilai secara ringkas oleh guru selepas kelas. The agent oleh guru is optional; dropping it is common in formal writing.