Techniques for determining if students, particularly ELLs, are comprehending a lesson

DQ1:

Effective teachers should adjust instruction based on the response of learners. What are some techniques for determining if students, particularly ELLs, are comprehending a lesson? What should a teacher do if they have ELLs who are not progressing linguistically after modifying instruction and practice activities? Provide at least two suggestions.

DQ2:

Do you believe that sound practices and strategies in planning, implementing, and managing instruction in support of ELLs should be different or unique in any way from the ones used to support other learners in the classroom? Why or why not? Provide examples and cite at least two scholarly resources to support your response.