agradece

v. thank; be grateful for; appreciate; acknowledge

v. thank, express gratitude

= offer + a word of thanks, thank, welcome, extend + Posesivo + thanks, be thankful.
Ex: In closing, I would like to offer a word of thanks to all the members of the Working Group who contributed so much of their time and effort to the development of this project.
Ex: In closing, I would like once again to thank all the members of the Working Group who contributed so much of their time and effort to the development of this project.
Ex: The decision to revert to standard spelling must have been widely welcomed in countries where DC is used but English is not the native language.
Ex: I would like to extend my thanks to our host who was kind enough to invite me.
Ex: Looking back from the present days of austerity one must be thankful that the EEC libraries were able to lay the foundations of strong collections in their respective fields.
----
* agradecer sinceramente = pay + Posesivo + deep respects.