Active galactic nuclei (AGN) can vary significantly in their rest-frame optical/UV continuum emission, and with strong associated changes in broad line emission, on much shorter timescales than predicted by standard models of accretion disks around supermassive black holes. Most such changing-look or changing-state AGN—and at higher luminosities, changing-look quasars (CLQs)—have been found via spectroscopic follow-up of known quasars showing strong photometric variability. The Time Domain Spectroscopic Survey of the Sloan Digital Sky Survey IV (SDSS-IV) includes repeat spectroscopy of large numbers of previously known quasars, many selected irrespective of photometric variability, and with spectral epochs separated by months to decades. Our visual examination of these repeat spectra for strong broad line variability yielded 61 newly discovered CLQ candidates. We quantitatively compare spectral epochs to measure changes in continuum and Hβ broad line emission, finding 19 CLQs, of which 15 are newly recognized. The parent sample includes only broad line quasars, so our study tends to find objects that have dimmed, i.e., turn-off CLQs. However, we nevertheless find four turn-on CLQs that meet our criteria, albeit with broad lines in both dim and bright states. We study the response of Hβ and Mg ii emission lines to continuum changes. The Eddington ratios of CLQs are low, and/or their Hβ broad line width is large relative to the overall quasar population. Repeat quasar spectroscopy in the upcoming SDSS-V black hole Mapper program will reveal significant numbers of CLQs, enhancing our understanding of the frequency and duty cycle of such strong variability, and the physics and dynamics of the phenomenon.

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Speech samples were obtained from Mexican‐American children who attended a monolingual school (N = 67) and Mexican‐American children who attended a bilingual school (N = 59) in the same school district. The children were asked to tell the story of a silent movie they had watched immediately before being interviewed. Their answers were recorded on tape and transcribed. Deviations from standard English were counted and categorized. The main findings of the study were (a) that the causes of deviations from standard English appeared to include the expected interference of Spanish as well as the improper application of standard English rules and the influence of nonstandard English dialects, and (b) that children in the bilingual school did not differ significantly from those in the monolingual school with respect to frequency of deviations from standard English.

Studentsstudying French at Levels4 ZI, and ZIZ in a rural and urban school setting indicated on a questionnaire their use of learning strategies associated with classroom behaviors, individual study tactics, and social interactional behaviors. Successful learning behaviors related to communicative abilities, reading performance, and achievement on a standaniized test were found to vary due to the nature of the task. Years of languagestudy also influenced the use/ need of dvferent sets of strategies. Eight stmteges contributed differentialIy to the overall success of these learners. (I) asking for clarification/verification, (2) using iderencing skills or deductive reasoning, (3) creating opportunities for pmctie (4) memorizing (5) using vocabulary learning techniques, (6) employing available linguktic knowledge and contextual cues, (7) being able to self-monitor performance, and (8) pmcticing.