What do "sempre senza sordino" and "attacca subito il seguente" mean?

These are Italian musical terms, Liz. The first means "always without a mute." The second, "Proceed at once to the following" -- passage, I suppose. I'm no expert on this subject, however, so someone else can explain the technicalities.

If an orchestral player encounters a passage marked "sempre senza sordino" - always without mutes - it is an indication that the composer thought he/she might be tempted to use mutes for that particular passage, and specifically doesn't want them used. ("spemre con sordino" - always with mutes - is a more common instruction, since a musician plays instruments without mutes by default.)

"Attaca subito il seguente" means that the following movement (or the following tempo change) is to be played immediately, without pause or delay of any kind. Though I can think offhand of only one place in the literature where such an instruction appears in the middle of a movement (the first movement of Beethoven's "Pathetique" piano sonata).

Thank-you both of you. Yes I think I understand now, they're both used in Beethoven's most boring piece, "Moonlight Sonata" (which I don't recommend you try to play!). I've never really understood what all of the music terminology means, even though my mother is a music teacher and I've been playing piano and flute since I was little!

Well, that's a whole different ballgame as far as the first instruction goes. The piano of Beethoven's day worked differently from the modern piano as we know it. (Beethoven and his music in particular had a lot to do with the development of the modern piano.)

I found it odd that a composer would go through so much trouble to instruct a player to keep the mutes off an instrument. But now that you bring up the Moonlisht Sonata I can understand perfectly. Beethoven intended for the entire first movement to be played wihout having the player take his/her foot off the pedal - the dampers on he strings were the "sordini", the mutes (as they stopped the sound of the intrument). On most pianos of Beethoven's day the ring tone was considerably short, and as the movement is a quiet piece of music it was easily possible to play the whole movement with the pedal and not have the notes sounding all mixed up. On today's piano that effect takes a lot more work to acheive, both in the fingers (which must have just the right attack on the keys) and in the right foot (which would only depress the pedal to exactly the right level).