Hello there ,
Thanks for writing your query,
is inflammation of lungs and it can be bacterial or viral .
Tongue lesions can be a secondary oral signs of pneumonia.other reasons include stress
ulcers which are long standing and painful, apthous ulcers, traumatic ulcers especially seen on sides on tongue.
Red flat lesion on tongue in the elderly group people usually associated with smoking
can be Erythroplakia
such lesions often show malignancy. do no panic but consult your doctor as soon as possible as such lesions should not be ignored.
mean time maintain good oral hygiene
.rinse your mouth with lukewarm salt water, apply topical numbing agents over the lesion
i hope this helps ,