I have been designing resources for many years as I worked with preschool and primary age youngsters with delayed or impaired speech and language skills. The resources using symbols are free. My latest resources which I have illustrated are extra tasks based on Marion Blank's Language Levels (previous ones have been free). They can be used with groups of mixed language ability and are reasonably priced.
A set of double-sided cards with pictures one side and mixed questions on the other for the adult to ask. Designed to give practice with responding appropriately to different question words, and picture description. Pictures can also be used as a prompt for writing sentences, and for pairing up with given sentences as a reading for meaning task.