美 
											[ˌɪndɪ'fætɪɡəbl]
																
										
							
																																	"an indefatigable advocate of equal rights"
																							"a tireless worker"
																							"unflagging pursuit of excellence"
																															
The American is..an indefatigable tryer.
出自: C. Chaplin
His indefatigable efforts to secure the guardianship.
出自: P. Gay