He had only experienced tangible and corporeal events in his life, but the hippy girl opened up his what side? Choose the most suitable option to answer the above question. Options：  A. insubstantial  B. mind  C. intangible  D. ethereal  E. spiritual
E

When you hair grows too long and heavy you can cut it to make it more what? Choose the most suitable option to answer the above question. Options：  A. very thin  B. more manageable  C. smooth  D. lightweight  E. long or short
D

The engineer put the new invention on the table in front of his bosses, he turned on his microphone and began his what of the product? Choose the most suitable option to answer the above question. Options：  A. stage  B. demonstration  C. record sound  D. parade  E. conference
B